Phra Bat Somdet Phra Poramentharamaha Vajiravudh Phra Mongkut Klao Chao Yu Hua (Thai: พระบาทสมเด็จพระปรเมนทรมหาวชิราวุธฯ พระมงกุฎเกล้าเจ้าอยู่หัว), or Phra Bat Somdet Phra Ramathibodi Si Sintharamaha Vajiravudh Phra Mongkut Klao Chao Yu Hua (Thai: พระบาทสมเด็จพระรามาธิบดีศรีสินทรมหาวชิราวุธฯ พระมงกุฎเกล้าเจ้าอยู่หัว), or Rama VI (1 January 1880 – 25 November 1925), was the sixth monarch of Siam under the House of Chakri, ruling from 1910 until his death. King Vajiravudh is known for his efforts to create and promote Siamese nationalism. His reign was characterized by Siam's movement further towards democracy and minimal participation in World War I.

Crown Prince Vajiravudh returned to Siam in 1902 and in 1904 became a temporary monk, in accordance with Siamese tradition. In 1906, his father Chulalongkorn travelled to Europe to seek treatment for his lung disease, and Chulalongkorn made Vajiravudh Regent of Siam. One of Crown Prince Vajiravudh's accomplishments during this regency was his supervision of the construction of the equestrian statue of King Chulalongkorn.

Chulalongkorn died on 23 October 1910, and Vajiravudh succeeded his father as king of Siam.

Even before his coronation, Vajiravudh initiated several reforms. He organized Siam's defence and established military academies. He created the rank of "general" for the first time in Siam, with his uncle, Prince Bhanurangsi Savangwongse as the first Siamese general.

His first act following his accession to the throne was to build the Royal Pages College, subsequently renamed Vajiravudh College by King Rama VII to honour his brother. It was built as an all-boy boarding school in the same tradition as English public schools such as Eton and Harrow. The school was built instead of a royal monastery, formerly a custom of Thai kings, as King Vajiravudh deemed that there were already too many temples in Bangkok. In his own hand written letter, King Vajiravudh wrote that "In the Royal Pages College, what I want is not so much to turn out model boys, all of the same standard, all brilliant scholars with thousands of marks each, as to turn out efficient young men—young men who will be physically and morally clean, and who will be looking forward keenly to take up whatever burden the future may lay upon them". Later he also raised the Civil Servant School to "Chulalongkorn Academy for Civil Officials", then Chulalongkorn University. Both Vajiravudh College and Chulalongkorn University still benefit from the funds that King Vajiravudh set aside for the use of the two elite institutions. He also improved Siamese healthcare systems and set up some of the earliest public hospitals in Siam, Vajira Hospital in 1912 and Chulalongkorn Hospital in 1914.

In 1911, he established the Boy Scouts (ลูกเสือ Tiger Cubs) in Siam (with an adult auxiliary called the Wild Tiger Corps [เสือป่า]), disbanded in the latter part of his reign. On 11 November 1911, Vajiravudh's coronation was held with visiting royals from Europe and Japan as guests, a first for Siam. Later that year, the first airplane was flown in Siam.

The early years of Vajiravudh's administration were largely dominated by his two uncles, Prince Damrong and Prince Devawongse, both of them Chulalongkorn's right hand men. However, the king disagreed with Prince Damrong, Minister of Interior, over Damrong's negotiation of the Anglo-Siamese Treaty of 1909 that ceded four sultanates to the British Empire.[2]

Vajiravudh reformed his father's monthon system by imposing the "paks" (Thai: ภาค) or "regions" over the administrative monthons. Each pak was governed by an Uparaja (viceroy) directly responsible to the king. The Uparaja presided over the intendants of monthons in the region—thus concentrating local administrative powers in his hands—much to the dismay of Prince Damrong.

Radicals expected a new constitution upon the coronation of Vajiravudh. However, no constitution was forthcoming. In 1911, the Wuchang Uprising that led to the fall of Qing dynasty prompted Siamese radicals to act. So, for the first time in Siam, an attempt was made to overthrow the monarchy and establish democracy.

The immediate cause, however, occurred even before Vajiravudh's coronation. In 1909, Crown Prince Vajiravudh ordered a Thai Royal Military Academy student who had had an argument with one of Vajiravudh's pages to be caned. Academy alumni were further provoked by Vajiravudh’s creation of the Wild Tiger Corps, seen by the army as a threat to their prerogatives.

The plotters were relatively young army and naval officers, students during the 1909 incident. The coup was planned for 1 April—the traditional Siamese New Years Day. They planned to elevate one of Vajiravudh's brothers to be the first President of Siam. They believed that, if the absolute monarchy were removed, Siam would achieve modernization as in Japan under Emperor Taishō. The coup leaders accused the king of devoting his time to writing and acting in theatrical plays with his companions. They also accused him of living a luxurious Western-style life, building Sanam Chan Palace and Lumphini Park, and owning expensive horses from Australia, while preaching austerity and nationalism to his subjects.

The coup plan was leaked. Captain Yut Kongyu, who was selected as the assassin by lottery, told Mom Chao Prawatpan, and then Prince Chakrabongse, of the intended coup. Prince Chakrabongse arrested all the conspirators. Their sentences were severe, ranging from execution to long-term imprisonment. However, Vajiravudh rescinded the punishments and released the plotters, saying that what they did was for the sake of the kingdom.

Rama VI inherited his father's plan of building a modern nation although he was skeptical. Disagreements occurred incessantly with "old aristocrats", many of whom were his relatives such as the celebrated Prince Damrong, his uncle, who took charge of the Ministry of Interior. As more and more corruption in the newly created provinces was reported, Rama VI created a viceroy system. Viceroys, appointed directly by the king, were sent to supervise provincial governors and local officials.

In 1913, Siam faced a financial crisis as the Chinese-Siamese Bank went bankrupt.[citation needed]

In 1914, Vajiravudh, having determined that the act providing for the invocation of martial law, first promulgated by his father in 1907, was not consistent with modern laws of war nor convenient for the preservation of the external or internal security of the state, changed to the modern form that, with minor amendments, continues in force.[3]

Also in 1914, the construction of Don Mueang Airport began. In the same year the Siamese government borrowed from the Federated Malay States to extend railways to the south. In 1915, Vajiravudh himself visited the southern provinces to oversee railway construction. The Bangkok railway station at Hua Lamphong was then established as a center of Siamese railroads. Prince Damrong eventually left the Ministry of Interior in 1915. In 1916, Vajiravudh appointed his half-brother, Prince of Kampangpetch, as the Head of the Railway Department.

In 1917, Vajiravudh established the Nakorn Sri Thammarat Regiment as his personal guard. In the same year Vajiravudh founded Chulalongkorn University, the first university in Siam, named in honor of his father. In 1918, Vajiravudh founded the Dusit Thani near Dusit Palace as an experimental site for democracy. The democratic institutions were imitated including elections, parliament, and the press. Vajiravudh himself acted as one of the citizens of Dusit Thani yet the city was perceived as another of Vajiravudh's theatrical conceits.

During 1918-1919 the price of rice soared. The government faced public criticism due to its tepid response. The major cause of the problem was the hoarding of rice. Chinese millers and rice merchants bought huge amounts of rice from farmers for export to Singapore, the largest rice market in the region. Price speculation was rampant. The government imposed a ban on rice exports. At the same time, public servants asked for higher wages due to the rising cost of living. The public, mainly the urban "middle-class", and Chinese traders became more and more unhappy with the government.

The Siamese Expeditionary Force with the tricolour flag of Siam in Paris, 1919.

On 22 July 1917 Vajiravudh declared war on Germany and Austria-Hungary.[4] He allied Siam with the Allied Powers and expelled German and Austrian officials from the Railway Department and Siam Commercial Bank. He also put the properties of the Central Powers under a Siamese government protectorate. Vajiravudh saw the war as an opportunity to create and promote Siamese nationalism. He changed the Flag of Siam from the elephant banner to the tricolor. King Vajiravudh is considered the father of Thai nationalism, which was later built upon by Field Marshal Phibunsongkhram and Sarit Dhanarajata. He introduced the practice of using the name Rama for the Chakri kings in deference to foreign practice.

Siamese troops were the only Southeast Asians in the European theatre (except for 140,000 Vietnamese colonial troops and workers drafted by the French).[5] The Siamese troops did not see much action though, as they arrived in Europe towards the end of the war. In any case, participation in the war allowed Siam to later negotiate with the Western powers as a partner, albeit a junior partner.[6]

In 1917, the price of silver rose and exceeded the face value of silver coins. The coins were then melted down and sold. The government solved this by changing the pure silver coin to alloy. Vajiravudh eventually forbade exports of Siamese coins. In 1918, the usage of 1-baht coins was nullified and 1-baht banknotes were introduced. Coins were recalled and kept as a national reserve. In 1919, Vajuravudh imposed a military-exemptation tax (Thai: เงินรัชชูปการ} nationwide including on the royal members. As the need for huge capital increased, a new bank, later known as the "Government Savings Bank", was founded in 1923.

Though the Siamese forces that joined the march at Versailles returned triumphant in 1919, the economic problems caused by World War I were serious. In the same year, drought hit Siam and rice shortages ensued. The government forbade the export of rice, the main Siamese export since the Bowring Treaty. Queen Mother Saovabha, Vajiravudh's mother, died in 1919. Siamese participation in World War I opened the way to reconciliation, first with the United States in 1920, then to redress the unequal treaties imposed by Western powers in the 19th century.

In spite of the financial crisis, railway constructions continued. The railway reached Narathiwat and was expanded north and east. The construction of Rama VI Bridge began in 1922 and the same year the railway reached Chiang Mai. However, the treasury was in such straits that a large loan from Britain was negotiated. Also in 1922, an insurgency occurred in Pattani over new taxation policies. It was readily suppressed by the Nakorn Sri Thammarat Regiment. In 1923, Vajiravudh announced his six principles in the governance of Pattani Province, emphasizing local freedom and tax measures.

Vajiravudh had been a king without a queen for about ten years. In 1920, he met Mom Chao Varnvimol at his theatre at Phayathai Palace. They were engaged and Princess Vanbimol was elevated to Princess Vallabha Devi. However, four months later in 1921, Vajiravudh nullified the engagement and pursued Princess Vallabha's sister, Princess Lakshamilavan, whom he engaged. However, the marriage was never held and the couple then separated.

In 1921, Vajiravudh married Prueang Sucharitakul, who was a daughter of Lord Suthammamontri and elevated her to Lady Sucharitsuda. He then married Sucharitsuda's sister, Prabai Sucharitakul, with the title of Lady Indrani. In 1922, Lady Indrani was elevated to Princess and Queen Indrasakdisachi. However, the queen suffered two miscarriages. In 1924, Vajiravudh married Krueakaew Abhaiwongse (Later Suvadhana), a daughter of Lord Aphaiphubet. Queen Indrasakdisachi was then demoted to Princess Consort Indrasakdisachi in 1925.

In 1924, Vajiravudh promulgated his Law of Succession, which has since become the code for Chakri dynasty successions. According to the law, the throne would be passed to the king's sons and grandsons. However, in the case of Vajiravudh who had no sons, the throne would pass to his eldest "true" brother, that is, a brother who shared the same mother, Queen Saovabha. The law gave priority to the descendants of princes born to Queen Saovabha, then to Queen Savang Vadhana, and then to Queen Sukumalmarsri. The law also forbade princes whose mother was foreign from the throne. This referred to his companion, Prince Chakrabongse, who had married a Russian woman. His son, Prince Chula Chakrabongse, was therefore barred from the throne.

In 1924, King Vajiravudh, accompanied by Suvadhana, visited the Federated Malay States. The reconciliation with European powers on unequal treaties progressed gradually, while the financial crisis was taking a great toll on Siam as another loan was taken from Britain and the firing of numerous government officials occurred. In 1925 Vajiravudh had to dissolve his Nakorn Sri Thammarat Regiment and merged provinces into larger units to lower maintenance costs.

In November 1925, it was announced that Vajiravudh fell ill.[7] Princess Consort Suvadhana was then pregnant. Vajiravudh then announced his succession instructions: if Princess Suvadhana gave birth to a son, the throne would go to him. If not, the throne would pass to his surviving brother, Prince Prajadhipok of Sukhothai. He barred Princess Inthrasaksachi from being interred with him in the future and instead granted that right to Princess Suvadhana. And Vajiravudh also barred his uncle, Prince Damrong, from the government.

On 24 November, Princess Suvadhana gave birth to a princess only two hours before Vajiravudh's death. Vajiravudh glimpsed of his sole daughter before his demise. The throne passed to his brother, Prajadhipok, who named Vajiravudh's daughter as Princess Bejaratana (Her Royal Highness Princess Bejaratana).

The king was well-versed in Sanskrit and Hindu literature, including the Ramayana and the Mahabharata epics. He translated many stories from the two epics into Thai and also wrote plays inspired by Hindu literature. He was influenced by Rama, the incarnation of Lord Vishnu and hero of the Ramayana epic, to the extent that he systemized and promoted the use of the name "Rama" as the (English) reign names of all Thai kings of the Bangkok (Rattanakosin) era. His own reign was dubbed as "Rama VI". (See Rama (Kings of Thailand))

In 1914 King Vajiravudh published in a Thai newspaper an article titled "The Jews of the East" where "It combined themes of European anti-Semitism with the fear of the 'Yellow Peril'" and accused Chinese immigrants in Thailand of excessive "racial loyalty and astuteness in financial matters." The king wrote, "Money is their God. Life itself is of little value compared with the leanest bank account."[8]